In early January Iranian media aired footage claiming Iran had captured two US-made surveillance drones over the past 17 months. Photograph: Reuters

Iran's Revolutionary Guard denied claims Sunday that it had brought downed a foreign surveillance drone on its soil, just hours after state media reported the aircraft's capture.

The official Islamic Republic News Agency had initially broken news of the apparent seizure of a unmanned drone on Saturday, quoting an army general as stating: "We have managed to bring down a drone of the enemy. This has happened before in our country."

But his comments were contradicted just hours later by the Revolutionary Guard, an elite branch of the Iranian military. Guard spokesman Yasin Hasanali told the Associated Press that the aircraft was in fact being used in an army drill as a supposed enemy aircraft.

Referring to the initial reports of a captured enemy drone, a Pentagon spokesman said he had seen the reports, noting that the Iranians did not specifically claim that the drone was American.

In the past, there have been incidents of Iran claiming to have seized US aircraft. In early January Iranian media said Iran had captured two miniature American-made surveillance drones over the past 17 months.

Several drone incidents over the past year or so have highlighted tension in the Gulf as Iran and the United States flex their military capabilities in a stand-off over Iran's disputed nuclear programme.

Iran said in January that lightweight RQ11 Raven drones were brought down by Iranian air defence units in separate incidents in August 2011 and November 2012.

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